The present invention relates to novel tyrosine alkoxyguanidine compounds that are inhibitors of alpha V (xcex1v) integrins, for example xcex1vxcex23 and xcex1vxcex25 integrins, their pharmaceutically acceptable salts, and pharmaceutical compositions thereof.
Integrins are cell surface glycoprotein receptors which bind extracellular matrix proteins and mediate cell-cell and cell-extracellular matrix interactions (generally referred to as cell adhesion events) (Hynes, R. O., Cell 69:11-25 (1992)). These receptors are composed of noncovalently associated alpha (xcex1) and beta (xcex2) chains which combine to give a variety of heterodimeric proteins with distinct cellular and adhesive specificities (Albeda, S. M., Lab. Invest. 68:4-14 (1993)). Recent studies have implicated integrins in the regulation of cellular adhesion, migration, invasion, proliferation, apoptosis and gene expression (Albeda, S. M., Lab. Invest. 68:4-14 (1993); Juliano, R., Cancer Met. Rev. 13:25-30 (1994); Ruoslahti, E. and Reed, J. C., Cell 77:477-478 (1994); and Ruoslahti, E. and Giancotti, F. G., Cancer Cells 1:119-126 (1989)).
One member of the integrin family which has been shown to play a significant role in a number of pathological conditions is the integrin xcex1vxcex23, or vitronectin receptor (Brooks, P. C., DNandP 10(8):456-461 (1997)). This integrin binds a variety of extracellular matrix components and other ligands, including fibrin, fibrinogen, fibronectin, vitronectin, laminin, thrombospondin, and proteolyzed or denatured collagen (Cheresh, D. A., Cancer Met. Rev. 10:3-10 (1991) and Shattil, S. J., Thromb. Haemost. 74:149-155 (1995)). The two related xcex1v integrins, xcex1vxcex25 and xcex1vxcex21 (also vitronectin receptors), are more specific and bind vitronectin (xcex1vxcex25) or fibronectin and vitronectin (xcex1vxcex21) exclusively (Horton, M., Int. J. Exp. Pathol. 71:741-759 (1990)). xcex1vxcex23 and the other integrins recognize and bind to their ligands through the tripeptide sequence Arg-Gly-Asp (xe2x80x9cRGDxe2x80x9d) (Cheresh, D. A., Cancer Met. Rev. 10:3-10 (1991) and Shattil, S. J., Thromb. Haemost. 74:149-155 (1995)) found within all the ligands mentioned above.
The xcex1vxcex23 integrin has been implicated in a number of pathological processes and conditions, including metastasis and tumor growth, pathological angiogenesis, and restenosis. For example, several studies have clearly implicated xcex1vxcex23 in the metastatic cascade (Cheresh, D. A., Cancer Met. Rev. 10:3-10 (1991); Nip, J. et al., J. Clin. Invest. 95:2096-2103 (1995); and Yun, Z., et al., Cancer Res. 56:3101-3111 (1996)). Vertically invasive lesions in melanomas are also commonly associated with high levels of xcex1vxcex23, whereas horizontally growing noninvasive lesions have little if any xcex1vxcex23 (Albeda, S. M., et al., Cancer Res. 50:6757-6764 (1990)). Moreover, Brooks et al. (in Cell 79:1157-1164 (1994)) have demonstrated that systemic administration of xcex1vxcex23 antagonists disrupts ongoing angiogenesis on chick chorioallantoic membrane (xe2x80x9cCAMxe2x80x9d), leading to the rapid regression of histologically distinct human tumors transplanted onto the CAM. These results indicate that antagonists of xcex1vxcex23 may provide a therapeutic approach for the treatment of neoplasia (solid tumor growth).
xcex1vxcex23 has also been implicated in angiogenesis, which is the development of new vessels from preexisting vessels, a process that plays a significant role in a variety of normal and pathological biological events. It has been demonstrated that xcex1vxcex23 is up-regulated in actively proliferating blood vessels undergoing angiogenesis during wound healing as well as in solid tumor growth. Also, antagonists of xcex1vxcex23 have been shown to significantly inhibit angiogenesis induced by cytokines and solid tumor fragments (Brooks, P. C., et al., Science 264:569-571 (1994); Enenstein, J. and Kramer, R. H., J. Invest. Dermatol. 103:381-386 (1994); Gladson, C. L., J. Neuropathol. Exp. Neurol 55:1143-1149 (1996); Okada, Y., et al., Amer. J. Pathol. 149:37-44 (1996); and Brooks, P. C., et al., J. Clin. Invest. 96:1815-1822 (1995)). Such xcex1vxcex23 antagonists would be useful for treating conditions that are associated with pathological angiogenesis, such as rheumatoid arthritis, diabetic retinopathy, macular degeneration, and psoriasis (Nicosia, R. F. and Madri, J. A., Amer. J. Pathol. 128:78-90 (1987); Boudreau, N. and Rabinovitch, M., Lab. Invest. 64:187-99 (1991); and Brooks, P. C., Cancer Met. Rev. 15:187-194 (1996)).
There is also evidence that xcex1vxcex23 plays a role in neointimal hyperplasia after angioplasty and restenosis. For example, peptide antagonists and monoclonal antibodies directed to both xcex1vxcex23 and the platelet receptor IIbxcex23 have been shown to inhibit neointimal hyperplasia in vivo (Choi, E. T., et al., J. Vasc. Surg. 19:125-134 (1994); and Topol, E. J., et al., Lancet 343:881-886 (1994)), and recent clinical trials with a monoclonal antibody directed to both IIbxcex23 and xcex1vxcex23 have resulted in significant reduction in restenosis, providing clinical evidence of the therapeutic utility of xcex23 antagonists (Topol, E. J., et al., Lancet 343:881-886 (1994)).
It has also been reported that xcex1vxcex23 is the major integrin on osteoclasts responsible for attachment to bone. Osteoclasts cause bone resorption. When bone resorbing activity exceeds bone forming activity, the result is osteoporosis, a condition which leads to an increased number of bone fractures, incapacitation and increased mortality. Antagonists of xcex1vxcex23 have been shown to be potent inhibitors of osteoclastic activity both in vitro (Sato, M., et al., J. Cell Biol. 111:1713-1723 (1990)) and in vivo (Fisher, J. E., et al., Endocrinology 132:1411-1413 (1993)).
Lastly, White (in Current Biology 3(9):596-599 (1993)) has reported that adenovirus uses xcex1vxcex23 for entering host cells. The xcex1vxcex23 integrin appears to be required for endocytosis of the virus particle and may be required for penetration of the viral genome into the host cell cytoplasm. Thus compounds which inhibit xcex1vxcex23 could be useful as antiviral agents.
The xcex1vxcex25 integrin has been implicated in pathological processes as well. Friedlander et al. have demonstrated that a monoclonal antibody for xcex1vxcex25 can inhibit VEGF-induced angiogenesis in rabbit cornea and chick chorioalloantoic membrane, indicating that the xcex1vxcex25 integrin plays a role in mediating growth factor-induced angiogenesis (Friedlander, M. C., et al., Science 270:1500-1502 (1995)). Compounds that act as xcex1vxcex25 antagonists could be used to inhibit pathological angiogenesis in tissues of the body, including ocular tissue undergoing neovascularization, inflamed tissue, solid tumors, metastases, or tissues undergoing restenosis.
Discovery of the involvement of xcex1vxcex23 and xcex1vxcex25 in such processes and pathological conditions has led to an interest in these integrins as potential therapeutic targets, as suggested in the preceding paragraphs. A number of specific antagonists of xcex1vxcex23 and xcex1vxcex25 that can block the activity of these integrins have been developed. One major group of such antagonists includes nonpeptide mimetics and organic-type compounds. For example, a number of organic non-peptidic mimetics have been developed that appear to inhibit tumor cell adhesion to a number of xcex1vxcex23 ligands, including vitronectin, fibronectin, and fibrinogen (Greenspoon, N., et al., Biochemistry 32:1001-1008 (1993); Ku, T. W., et al., J. Amer. Chem. Soc. 115:8861-8862 (1993); Hershkoviz, R., et al., Clin. Exp. Immunol. 95:270-276 (1994); and Hardan, L., et al., Int. J. Cancer 55:1023-1028 (1993)).
Additional organic compounds developed specifically as xcex1vxcex23 or xcex1vxcex25 integrin antagonists or as compounds useful in the treatment of xcex1v-mediated conditions have been described in several recent publications.
For example, U.S. Pat. No.5,741,796, issued Apr. 21, 1998, discloses pyridyl and naphthyridyl compounds for inhibiting osteoclast-mediated bone resorption.
PCT Published Application WO 97/45137, published Oct. 9, 1997, discloses non-peptide sulfotyrosine derivatives, as well as cyclopeptides, fusion proteins, and monoclonal antibodies, that are useful as inhibitors of xcex1vxcex23 integrin-mediated angiogenesis.
PCT Published Application WO 97/36859, published Oct. 9, 1997, discloses para-substituted phenylpropanoic acid derivatives of the general formula: 
where A is: 
B isxe2x80x94CH2CONHxe2x80x94, xe2x80x94CONR52xe2x80x94(CH2)pxe2x80x94, xe2x80x94C(O)Oxe2x80x94, xe2x80x94SO2NHxe2x80x94, xe2x80x94CH2Oxe2x80x94, or xe2x80x94OCH2xe2x80x94;
Y1 is selected from the group consisting of Nxe2x80x94R2, O and S;
Y3 and Z3 are independently selected from the group consisting of H, alkyl, aryl, cycloalkyl and aralkyl, or Y3 and Z3 taken together with C form a carbonyl;
R50 is selected from the group consisting of H, alkyl, aryl, carboxyl derivative and xe2x80x94CONHCH2CO2R53, wherein R53 is H or lower alkyl; and
R51 is selected from the group consisting of H, alkyl, carboxyl derivatives, 
wherein R54 is selected from the group consisting of H, alkyl, cycloalkyl, aryl, aralkyl, aralkenyl and aryl substituted by one or more alkyl or halo; and wherein R55 is selected from the group consisting of N-substituted pyrrolidinyl, piperidinyl and morpholinyl.
The publication also discloses the use of the compounds as xcex1vxcex23 integrin antagonists.
PCT Published Application WO 97106791, published Feb. 1997, discloses methods for inhibition of angiogenesis in tissue using vitronectin xcex1vxcex25 antagonists.
More recently, PCT Published Application WO 97/23451, published Jul. 3, 1997, discloses tyrosine derivatives of the general formula: 
wherein
X is C1-6alkylene or 1,4-piperidyl;
Y is absent, O, CONH or xe2x80x94Cxe2x89xa1Cxe2x80x94;
R1 is H, CN, N3, NH2, H2Nxe2x80x94C(xe2x95x90NH), or H2Nxe2x80x94C(xe2x95x90NH)xe2x80x94NH, where the primary amino groups can also be provided with conventional amino protective groups;
R2 and R3 are independently H, A, Axe2x80x94SO2xe2x80x94, Arxe2x80x94SO2xe2x80x94, camphor-10-SO2xe2x80x94, COOA or a conventional amino protective group;
A and R4 are independently H, C1-10alkyl, or benzyl; and
Ar is phenyl or benzyl, each of which is unsubstituted or monosubstituted by CH3;
and their physiologically acceptable salts.
The disclosed compounds are described as xcex1v-integrin inhibitors (especially xcex1vxcex23 inhibitors) useful in the treatment of tumors, osteoporoses, and osteolytic disorders and for suppressing angiogenesis.
PCT Published Application WO 98/00395, published Jan. 8, 1998, discloses novel tyrosine and phenylalanine derivatives as xcex1v integrin and GPIIb/IIIa antagonists having the general formula: 
wherein
X can be, among other groups, alkyl, aryl or cycloalkyl;
Y and Z can be alkyl, O, S, NH, C(xe2x95x90O), CONH, NHCO, C(xe2x95x90S), SO2NH, NHSO2, CAxe2x95x90CAxe2x80x2 or xe2x80x94Cxe2x89xa1Cxe2x80x94;
R1 can be H2Nxe2x80x94C(xe2x95x90NH) or H2Nxe2x80x94(Cxe2x95x90NH)xe2x80x94NH;
R2 is A, aryl or aralkyl;
R3 is hydrogen or A;
R4 is hydrogen, halogen, OA, NHA, NAAxe2x80x2, xe2x80x94NH-Acyl, xe2x80x94O-Acyl, CN, NO2, SA, SOA, SO2A, SO2Ar or SO3H; and
A and Axe2x80x2 can be hydrogen, alkyl or cycloalkyl.
The publication discloses the use of the compounds in pharmaceutical preparations for the treatment of thrombosis, infarction, coronary heart disease, tumors, arteriosclerosis, infection and inflammation.
A need continues to exist for non-peptide compounds that are potent and selective integrin inhibitors, and which possess greater bioavailability or fewer side-effects than currently available integrin inhibitors.
The present invention is directed to novel tyrosine alkoxyguanidine compounds having Formula IV (below). Also provided is a process for preparing compounds of Formula IV. The novel compounds of the present invention exhibit inhibition of xcex1vxcex23 and xcex1vxcex25 integrin receptor binding. Also provided is a method of treating xcex1vxcex23 integrin- and xcex1vxcex25 integrin-mediated pathological conditions such as tumor growth, metastasis, osteoporosis, restenosis, inflammation, macular degeneration, diabetic retinopathy, and rheumatoid arthritis in a mammal in need of such treatment comprising administering to said mammal an effective amount of a compound of Formula IV. Further provided is a pharmaceutical composition comprising a compound of Formula IV and one or more pharmaceutically acceptable carriers or diluents.
The present invention is directed to compounds of Formula IV: 
and pharmaceutically acceptable salts thereof; wherein
R1 and R2 independently represent hydrogen, alkyl, aralkyl, R12SO2, R12OOC, or R12CO, where R12 is (i) hydrogen, or (ii) alkyl, cycloalkyl, camphor-10-yl, alkenyl, alkynyl, heterocycle, aryl, aralkyl, or aralkenyl, any of which can be optionally substituted by one or more alkyl, alkenyl, aryl, aryloxy (further optionally substituted by nitro, halo, or cyano), aralkyl, aryldiazenyl (further optionally substituted by amino, alkylamino, or dialkylamino), alkoxy, haloalkyl, haloalkoxy, alkylcarbonylamino, alkylsulfonyl, mono- or di-alkylamino, hydroxy, carboxy, cyano, nitro, halo, or a heteroaryl which is optionally substituted with one or more alkyl, haloalkyl, or halo;
and when R1 or R2 is R12CO, then R12 can also be N-attached pyrrolidinyl, piperidinyl or morpholinyl;
R3 is hydrogen or a functionality which acts as a prodrug (i.e., converts to the active species by an endogenous biological process such as an esterase, lipase, or other hydrolases), such as alkyl, aryl, aralkyl, dialkylaminoalkyl, 1-morpholinoalkyl, 1-piperidinylalkyl, pyridinylalkyl, alkoxy(alkoxy)alkoxyalkyl, or (alkoxycarbonyl)oxyethyl;
R4 is hydrogen, alkyl, aralkyl, aryl, hydroxyalkyl, aminoalkyl, monoalkylaminoalkyl, dialkylaminoalkyl, carboxyalkyl, hydroxy, alkoxy, aralkoxy, aryloxy, heteroaryloxy, or mono- or di- alkylamino;
R5, R6, and R7 are independently hydrogen, alkyl, aralkyl, aryl, hydroxyalkyl, aminoalkyl, monoalkylaminoalkyl, dialkylaminoalkyl or carboxyalkyl;
or R4 and R5 are taken together to form xe2x80x94(CH2)yxe2x80x94, where y is zero (a bond), 1 or 2, while R6 and R7 are defined as above; or R4 and R7 are taken together to form xe2x80x94(CH2)qxe2x80x94, where q is zero (a bond), or 1 to 8, while R5 and R6 are defined as above; or R5 and R6 are taken together to form xe2x80x94(CH2)rxe2x80x94, where r is 2-8, while R4 and R7 are defined as above;
R8 is hydrogen, alkyl, aralkyl, hydroxyalkyl, aminoalkyl, monoalkylaminoalkyl, dialkylaminoalkyl or carboxyalkyl;
R9, R10, and R11 are independently hydrogen, alkyl, aralkyl, hydroxy, alkoxy, aryloxy, aralkoxy, alkoxycarbonyloxy, cyano or xe2x80x94COORw;
Rw is alkyl, cycloalkyl, phenyl, benzyl, 
where Ra and Rb are independently hydrogen, alkyl, alkenyl or phenyl; Rc is hydrogen, alkyl, alkenyl or phenyl; Rd is hydrogen, alkyl, alkenyl or phenyl; and Re is aralkyl or alkyl;
n is from zero to 8; m is from zero to 4; provided that n is other than zero when R4 is hydroxy, alkoxy, aralkoxy, aryloxy, heteroaryloxy, or mono- or di-alkylamino.
Preferred compounds of the present invention are those of Formula IV wherein:
R1 and R2 independently represent hydrogen, C1-6alkyl, C6-10ar(C1-6)alkyl, R12SO2, R12OOC or R12CO, where R12 is hydrogen, C1-6alkyl, C6-10ar(C1-6)alkyl, C4-7cycloalkyl(C1-4)alkyl, camphor-10-yl, or C6-10aryl substituted by one or more (C1-6)alkyl, (C2-6)alkenyl, C6-10aryl, C6-10ar(C1-6)alkyl, C6-10 aryloxy (further optionally substituted by nitro, halo, or cyano), C6-10 aryldiazenyl (further optionally substituted by amino, C1-4alkylamino or di (C1-4)alkylamino), C1-6 alkoxy, halo(C1-6)alkyl, halo(C1-6)alkoxy, C1-6 alkylcarbonylamino, C1-6alkylsulfonyl, mono- or di-(C1-6)alkylamino, hydroxy, carboxy, cyano, nitro, halo, or a heteroaryl which is optionally substituted with one or more C1-6alkyl, halo(C1-6)alkyl, or halo;
and when R1 or R2 is R12CO, then R12 can also be N-attached pyrrolidinyl, piperidinyl or morpholinyl.
Preferred values of R1 include hydrogen and methyl.
Preferred values of R2 include hydrogen, t-butylcarbonyl, butylsulfonyl, propylsulfonyl, benzylsulfonyl, pentylsulfonyl, 4-tolylsulfonyl, and camphor-10-sulfonyl.
Especially preferred compounds are those of Formula IV wherein:
R1 is hydrogen; and
R2 is R12SO2, where R12 is hydrogen, C1-6alkyl, C4-7cycloalkyl, camphor-10-yl, (C2-6)alkenyl, (C2-6)alkynyl, thienyl, thiazolyl, benzo[b]thiophenyl, pyrazolyl, chromanyl, imidazolyl, benzo[2,3-c]1,2,5-oxadiazole, C6-10aryl, C6-10ar(C1-6)alkyl, or C6-10 ar(C2-6alkenyl, any of which can be optionally substituted by one or more C1-6alkyl, C2-6alkenyl, C6-10aryl, C6-10aryloxy (further optionally substituted by nitro, halo, or cyano), C6-10ar(C6-10)alkyl, 4-dimethylaminophenyldiazenyl, C1-6alkoxy, halo(C1-6)alkyl, halo(C1-6)alkoxy, C1-6alkylcarbonylamino, C1-6alkylsulfonyl, mono- or di-(C1-6)alkylamino, hydroxy, carboxy, cyano, nitro, halo, or pyrazolyl which is optionally substituted with one or more C1-6alkyl, halo(C1-6)alkyl, or halo.
Suitable values of R12 include methyl, butyl, chloropropyl, phenyl, benzyl, methylphenyl, ethylphenyl, propylphenyl, butylphenyl, tert-butylphenyl, pentylphenyl, phenylphenyl, camphoryl, nitrophenyl, nitrophenylmethyl, cyanophenyl, chlorophenyl, fluorophenyl, bromophenyl, trifluoromethylphenyl, trifluoromethoxyphenyl, acetylaminophenyl, butoxyphenyl, biphenyl, vinylphenyl, methoxyphenyl, methylsulfonylphenyl, 4-(3-chloro-2-cyanophenoxy)phenyl, 4-(1,1-dimethylpropyl)phenyl, 6-chloro-2-methylphenyl, 2-methyl-5-nitrophenyl, 2,3,4-trichlorophenyl, 4-bromo-2,5-difluorophenyl, 5-bromo-2-methoxyphenyl, 2-chloro-5-(trifluoromethyl)-phenyl, 4-(2-chloro-6-nitrophenoxy, 4-bromo-2-(trifluoromethoxy)-phenyl, 3-chloro-2-cyanophenyl, 3-chloro-2-methylphenyl, 2-methyl-5-nitrophenyl, 4-methyl-3-nitrophenyl, 2,5-bis(2,2,2-trifluoroethoxy)phenyl, 2-chloro-4-(trifluoromethyl)phenyl, 4-chloro-2,5-dimethylphenyl, 5-chloro-2-methoxyphenyl, 4,6-dichloro-2-methylphenyl, 4-bromo-2-methylphenyl, 4-bromo-2-ethylphenyl, 2,4,6-trimethylphenyl, 2,3,4,5,6-pentamethylphenyl, 3,5-dichloro-2-hydroxyphenyl, 2,5-dimethoxyphenyl, 3,4-dimethoxyphenyl, 2,5-dimethylphenyl, 2-chloro4-(trifluoromethyl)phenyl, 3,5-dichlorophenyl, 2,6dichlorophenyl, 2,3-dichlorophenyl, 2,5-dichlorophenyl, 3,4-dichlorophenyl, 2,4-dichlorophenyl, 3,4dibromophenyl, 2,6-difluorophenyl, 3,4-difluorophenyl, 2,4,5-trichlorophenyl, 2,4,6-trichlorophenyl, 2,4,6-tris(methylethyl)phenyl, 4-bromo-2-ethylphenyl, 4-chloro-3-nitrophenyl, 2-methoxy-5-methylphenyl, 5-fluoro-2-methylphenyl, 4-methoxy-2,3,6-trimethylphenyl, 3-chloro-4-methylphenyl, 1-methylimidazol-4-yl,carboxyphenyl, naphthyl, 2,2,5,7,8-pentamethyl-chroma6-yl, thienyl, 5-chloro-2-thienyl, 3-bromo-5-chloro-2-thienyl, 4-bromo-2,5-dichloro-3-thienyl, 4,5-dibromo-2-thienyl, 4-bromo-5-chloro-2-thienyl, 5-bromo-2-thienyl, 2,5-dichloro-3-thienyl, 2-(acetylamino)-4-methyl-1,3-thiazol-5-yl, 5-chloro-1,3-dimethylpyrazol-4-yl, 5-[1-methyl-5-(trifluoromethyl)-pyrazol-3-yl]-2-thienyl, 5-chloro-3-methylbenzo[b]thiophen-2-yl, 5-chloro-1,3-dimethylpyrazol-4-yl, 4-[4-(dimethylaminophenyl)diazenyl]phenyl, 4-[3-(amidinoaminooxy)propoxy]phenyl, benzo[2,3-c]1,2,5-oxadiazol-4-yl, and 2-phenylvinyl.
Preferred R3 groups include hydrogen, C1-6alkyl and benzyl.
Preferred values of R4 include hydrogen, C1-6alkyl, C6-10ar(C1-6)alkyl, C1-6aryl, C2-10hydroxyalkyl, C2-10aminoalkyl, C2-7carboxyalkyl, mono(C1-4alkyl)amino(C1-8)alkyl, and di(C1-4alkyl)amino(C1-8)alkyl. Suitable values of R4 include methyl, ethyl, propyl, n-butyl, benzyl, phenylethyl, 2-hydroxyethyl, 3-hydroxypropyl, 4-hydroxybutyl, 2-aminoethyl, 2-carboxymethyl, 3-carboxyethyl, 4-carboxypropyl and 2-(dimethylamino)ethyl.
Preferred compounds are those of Formula IV in which R5, R6 and R7 are independently hydrogen, C1-6alkyl, C6-10ar(C1-6)alkyl, C1-6aryl, C2-10hydroxyalkyl or C2-7carboxyalkyl. Useful values of R5, R6, and R7 include hydrogen, methyl, ethyl, propyl, n-butyl, benzyl, phenylethyl, 2-hydroxyethyl, 3-hydroxypropyl, 4-hydroxybutyl, 2-carboxymethyl, 3-carboxyethyl and 4-carboxypropyl. In the most preferred embodiments, R5, R6 and R7 are each hydrogen.
Preferred values of R8 include hydrogen or C1-6alkyl.
Preferred values of R9, R10 and R11 in Formula IV include hydrogen, hydroxy, C1-6alkyl, C1-6alkoxy, cyano or xe2x80x94CO2Rw, where Rw, in each instance, is preferably one of C1-4alkyl, C4-7cycloalkyl, phenyl, or benzyl. Suitable values of R9, R10 and R11 include hydrogen, methyl, ethyl, propyl, n-butyl, hydroxy, methoxy, ethoxy, cyano, xe2x80x94CO2CH3, xe2x80x94CO2CH2CH3 and xe2x80x94CO2CH2CH2CH3. In the most preferred embodiments, R9, R10 and R11 are each hydrogen.
Preferred values of m in Formula IV include zero to 6, more preferably zero to 4, and most preferably zero, 1, or 2.
Preferred values of m include zero to 4, and most preferably zero, 1, or 2.
It is also to be understood that the present invention is considered to include stereoisomers as well as optical isomers, e.g. mixtures of enantiomers as well as individual enantiomers and diastereomers, which arise as a consequence of structural asymmetry in selected compounds of the present series.
When any variable occurs more than one time in any constituent or in Formula IV, its definition on each occurrence is independent of its definition at every other occurrence. Also, combinations of substituents and/or variables are permissible only if such combinations result in stable compounds.
The term xe2x80x9calkylxe2x80x9d as employed herein by itself or as part of another group refers to both straight and branched chain radicals of up to 12 carbons, such as methyl, ethyl, propyl, isopropyl, butyl, t-butyl, isobutyl, pentyl, hexyl, isohexyl, heptyl, 4,4-dimethylpentyl, octyl, 2,2,4-trimethylpentyl, nonyl, decyl, undecyl, dodecyl.
The term xe2x80x9calkenylxe2x80x9d is used herein to mean a straight or branched chain radical of 2-20 carbon atoms, unless the chain length is limited thereto, including, but not limited to, ethenyl, 1-propenyl, 2-propenyl, 2-methyl-1-propenyl, 1-butenyl, 2-butenyl, and the like. Preferably, the alkenyl chain is 2 to 10 carbon atoms in length, more preferably, 2 to 8 carbon atoms in length most preferably from 2 to 4 carbon atoms in length.
The term xe2x80x9calkoxyxe2x80x9d is used herein to mean a straight or branched chain radical of 1 to 20 carbon atoms, unless the chain length is limited thereto, bonded to an oxygen atom, including, but not limited to, methoxy, ethoxy, n-propoxy, isopropoxy, and the like. Preferably the alkoxy chain is 1 to 10 carbon atoms in length, more preferably 1 to 8 carbon atoms in length.
The term xe2x80x9carylxe2x80x9d as employed herein by itself or as part of another group refers to monocyclic or bicyclic aromatic groups containing from 6 to 12 carbons in the ring portion, preferably 6-10 carbons in the ring portion, such as phenyl, naphthyl or tetrahydronaphthyl.
The term xe2x80x9caryloxyxe2x80x9d as employed herein by itself or as part of another group refers to monocyclic or bicyclic aromatic groups containing from 6 to 12 carbons in the ring portion, preferably 6-10 carbons in the ring portion, bonded to an oxygen atom. Examples include, but are not limited to, phenoxy, naphthoxy, and the like.
The term xe2x80x9cheteroarylxe2x80x9d as employed herein refers to groups having 5 to 14 ring atoms; 6, 10 or 14 xcfx80 electrons shared in a cyclic array; and containing carbon atoms and 1, 2 or 3 oxygen, nitrogen or sulfur heteroatoms (where examples of heteroaryl groups are: thienyl, benzo[b]thienyl, naphtho[2,3-b]thienyl, thianthrenyl, furyl, pyranyl, isobenzofuranyl, benzoxazolyl, chromenyl, xanthenyl, phenoxathiinyl, 2H-pyrrolyl, pyrrolyl, imidazolyl, pyrazolyl, pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl, indolizinyl, isoindolyl, 3H-indolyl, indolyl, indazolyl, purinyl, 4H-quinolizinyl, isoquinolyl, quinolyl, phthalazinyl, naphthyridinyl, quinazolinyl, cinnolinyl, pteridinyl, 4aH-carbazolyl, carbazolyl, xcex2-carbolinyl, phenanthridinyl, acridinyl, perimidinyl, phenanthrolinyl, phenazinyl, isothiazolyl, phenothiazinyl, isoxazolyl, furazanyl and phenoxazinyl groups).
The term xe2x80x9caralkylxe2x80x9d or xe2x80x9carylalkylxe2x80x9d as employed herein by itself or as part of another group refers to C1-6alkyl groups as discussed above having an aryl substituent, such as benzyl, phenylethyl or 2-naphthylmethyl.
The term xe2x80x9ccycloalkylxe2x80x9d as employed herein by itself or as part of another group refers to cycloalkyl groups containing 3 to 9 carbon atoms. Typical examples are cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl and cyclononyl.
The term xe2x80x9cheterocyclexe2x80x9d as used herein, except where noted, represents a stable 5- to 7-membered mono- or bicyclic or stable 7- to 10-membered bicyclic heterocyclic ring system any ring of which may be saturated or unsaturated, and which consists of carbon atoms and from one to three heteroatoms selected from the group consisting of N, O and S, and wherein the nitrogen and sulfur heteroatoms may optionally be oxidized, and the nitrogen heteroatom may optionally be quaternized, and including any bicyclic group in which any of the above-defined heterocyclic rings is fused to a benzene ring. Especially useful are rings containing one oxygen or sulfur, one to three nitrogen atoms, or one oxygen or sulfur combined with one or two nitrogen atoms. The heterocyclic ring may be attached at any heteroatom or carbon atom which results in the creation of a stable structure. Examples of such heterocyclic groups include piperidinyl, piperazinyl, 2-oxopiperazinyl, 2-oxopiperidinyl, 2-oxopyrrolodinyl, 2-oxoazepinyl, azepinyl, pyrrolyl, 4-piperidonyl, pyrrolidinyl, pyrazolyl, pyrazolidinyl, imidazolyl, imidazolinyl, imidazolidinyl, pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl, oxazolyl, oxazolidinyl, isoxazolyl, isoxazolidinyl, morpholinyl, thiazolyl, thiazolidinyl, isothiazolyl, quinuclidinyl, isothiazolidinyl, indolyl, quinolinyl, isoquinolinyl, chromanyl, benzimidazolyl, thiadiazoyl, benzopyranyl, benzothiazolyl, benzo[b]thiophenyl, benzo[2,3-c]1,2,5-oxadiazolyl, benzoxazolyl, furyl, tetrahydrofuryl, tetrahydropyranyl, thienyl, benzothienyl, thiamorpholinyl, thiamorpholinyl sulfoxide, thiamorpholinyl sulfone, and oxadiazolyl. Morpholino is the same as morpholinyl.
The term xe2x80x9chalogenxe2x80x9d or xe2x80x9chaloxe2x80x9d as employed herein by itself or as part of another group refers to chlorine, bromine, fluorine or iodine with chlorine being preferred.
The term xe2x80x9cmonoalkylaminexe2x80x9d as employed herein by itself or as part of another group refers to an amino group which is substituted with one alkyl group having from 1 to 6 carbon atoms.
The term xe2x80x9cdialkylaminexe2x80x9d as employed herein by itself or as part of another group refers to an amino group which is substituted with two alkyl groups, each having from 1 to 6 carbon atoms.
The term xe2x80x9chydroxyalkylxe2x80x9d as employed herein refers to any of the above alkyl groups substituted by one or more hydroxyl moieties.
The term xe2x80x9ccarboxyalkylxe2x80x9d as employed herein refers to any of the above alkyl groups substituted by one or more carboxylic acid moieties.
The term xe2x80x9chaloalkylxe2x80x9d as employed herein refers to any of the above alkyl groups substituted by one or more chlorine, bromine, fluorine or iodine with fluorine and chlorine being preferred, such as chloromethyl, iodomethyl, trifluoromethyl, 2,2,2-trifluoroethyl, and 2-chloroethyl.
The term xe2x80x9chaloalkoxyxe2x80x9d as used herein refers to any of the above haloalkyl groups bonded to an oxygen atom, such as trifluromethoxy, trichloromethoxy, and the like.
Another aspect of the present invention is a process for preparing a tyrosine alkoxyguanidine compound of Formula IV, comprising reacting a compound of Formula V: 
or a salt, hydrate, solvate or prodrug thereof, wherein R1, R2, R3, R4, R5, R6, R7, m and n are as defined above, with a deprotection reagent and a guanidinylating reagent, to form a compound of Formula VI: 
or a salt, hydrate, solvate or prodrug thereof, where R1, R2, R3, R4, R5, R6, R7, R9, R10, m and n are as defined as above. Preferred deprotection reagents include hydrazine or methylamine. Preferred guanidinylating reagents include aminoiminosulfonic acid, 1H-pyrazole-1-carboxamidine hydrochloride, N,Nxe2x80x2-bis(tert-butoxycarbonyl)-S-methylisothiourea, or N-R9, N-R10-1H-pyrazole-1-carboxamidine, where R9 and R10 are defined as above.
The compounds of the present invention may be prepared by the general procedures outlined in Schemes I, II, and III (below), where R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11,R12, Rw, n, and m are as defined above. 
Scheme I outlines the synthetic steps to produce compounds of the present invention where R1 is R12OOCxe2x80x94 or R12COxe2x80x94 or R12CH2xe2x80x94. The carboxyl group of the tyrosine 1 is protected as an ester by methods well known in the art (Bodanszky, M. and Bodanszky, A., The Practice of Peptide Synthesis, Springer-Verlag, Berlin (1984)). The amine 2 is reacted with acyl chlorides (R12COCl) in the presence of a suitable base such as a tertiary amine to produce carboxamides 3 (R1=R12CO). Alternatively, the carboxamides 3 may be produced by the reaction of 2 with carboxylic acids (R12COOH) by any of the known peptide coupling reagents, such as 1,3-dicyclohexylcarbodiimide or Castro""s reagent (BOP) (Castro, B., et al., Tetrahedron Lett. 1219 (1975)). Still alternatively, the amines 2 can be converted to carbamates 3 (R1=R12OOC) by reaction with chloroformates (R12OCOCl) in the presence of a base, such as a tertiary amine. Still alternatively, reductive animation of 2 can be achieved by reaction with an aldehyde (R12COH) under reducing conditions. The preferred reducing agent is tetramethylammonium triacetoxyborohydride. Alternatively, sodium triacetoxyborohydride or sodium cyanoborohydride may be used. Still alternatively, reductive amination may be carried out by forming an imine (Schiff base) between the amine and the carbonyl component using a catalytic amount of acid such as p-toluenesulfonic acid, followed by reduction with sodium cyanoborohydride. The alkylated amines 3 (R1=R12CH2xe2x80x94) can be further converted to dialkylated amines 4 by a repetition of the reductive amination step above to produce R2=R12CH2xe2x80x94. Still alternatively, the imine may be reduced using catalytic hydrogenation using a catalyst such as palladium on carbon in a standard solvent such as ethanol. As an alternative to reduction methods, the amine 2 may be reacted with R12CH2L, where L is a reactive leaving group, such as a halide or sulfonate.
The phenolic functionality of 4 is coupled to 5, where L is a reactive leaving group such as halide or sulfonate, under basic conditions, such as cesium carbonate in a solvent such as N,N-diethylformamide. The alcohol functionality may be protected with pa, an orthogonally selective functionality to the ester functionality (i.e., benzyl ethers would not be used with a benzyl ester). Removal of the optional alcohol protecting group pa is routinely accomplished using the reaction conditions well known in the art. For example, deprotection of benzyl ethers maybe effected through catalytic hydrogenation using palladium on carbon as a catalyst in solvents such as ethanol or tetrahydrofuran. Deprotection of an acetate protecting group is accomplished by basic hydrolysis, most preferably with sodium hydroxide in aqueous tetrahydrofuran. Alternatively, the phenolic functionality of 4 may be coupled to 5 (for L=OH) using a Mitsunobu coupling procedure (Mitsunobu, O., Synthesis 1 (1981)), where pa may be a suitable alcohol protecting group. Alternatively, suitable diols (Pa=H) may be used in the Mitsunobu reaction. Preferred coupling conditions include using a trialkylphosphine or triarylphosphine, such as tri-n-butylphosphine or triphenylphosphine, in a suitable solvent, such as tetrahydrofuran or dichloromethane, and an azodicarbonyl reagent, such as diethyl azodicarboxylate or 1,1xe2x80x2-(azodicarbonyl)dipiperidine.
Alcohol 6 is converted to 7 employing a Mitsunobu reaction with an N-hydroxycyclic imide derivative such as N-hydroxyphthalimide. Unveiling of the phthalimide protecting group of 7 is accomplished using standard conditions well known in the art (Greene, T. W. and Wuts, P. G. M., Protective Groups in Organic Synthesis, 2nd edition, John Wiley and Sons, Inc. New York (1991)), for example using hydrazine or methylamine. Alternatively, sodium borohydride in a mixture of an appropriate alcohol (e.g., ethanol/water) followed by acidification.
Guanidinylation of the resulting alkoxyamine to 8 is achieved using standard reagents such as aminoiminosulfonic acid (Miller, A. E. and Bischoff, J. J. Synthesis 777 (1986)), or 1H-pyrazole-1-carboxamidine hydrochloride (Bernatowicz, M. S. et al., J. Org. Chem. 57 (8), 2497 (1992)), or with substituted guanidinylating reagents such as N,Nxe2x80x2-bis(tert-butoxycarbonyl)-S-methylisothiourea (Bergeron, R. J. and McManis, J. S., J. Org. Chem. 52:1700 (1987)) or N-R9, N-R10-1H-pyrazole-1-carboxamidine, where R9 and R10) are defined as above for Formula IV. When R9and R10 are protecting groups, for example t-butyloxycarbonyl (Boc), the compound can be optionally reacted with R11OH using standard Mitsunobu reaction condition as reviewed above to produce alkylated compounds 9. These protecting groups can be optionally removed by treatment with acid, usually trifluoroacetic acid in a suitable solvent such as dichloromethane or water, or by HCl gas dissolved in a suitable solvent, such as 1,4-dioxane to produce targeted compounds 10.
Scheme II outlines the synthetic steps to produce compounds of the present invention where R1of Formula IV is R12SO2xe2x80x94. Thus, compound 8, where R1 is N-benzyloxycarbonyl (Cbz) is removed by catalytic hydrogenation using a catalyst such as palladium on carbon and hydrogen to reveal the amino functionality, which is subsequently sulfonylated with sulfonyl chlorides (R12SO2Cl) or sulfoanhydrides (R12SO2)2O to produce sulfonamides 11. The acidic nature of the sulfonamide nitrogen allows alkylations to occur under basic conditions. Thus, reaction with a base such as potassium carbonate and R2X, where X is a reactive leaving group such as a halide or sulfonate in a suitable solvent such as acetonitrile provides alkylated sulfonamides 12. When R9 and R10 are protecting groups, for example t-butyloxycarbonyl (Boc), the compound can be optionally reacted with R11OH using standard Mitsunobu reaction condition as reviewed above to produce alkylated compounds 13. These protecting groups can be optionally removed by treatment with acid, usually trifluoroacetic acid in a suitable solvent such as dichloromethane or water, or by HCl gas dissolved in a suitable solvent, such as 1,4-dioxane to produce targeted compounds 14.
Further functionalization of the amidinoaminooxy group in 10 and 14 (where R1 is R12SO2) is described in Scheme III. The aminooxy nitrogen of 10 and 14 may be optionally alkylated using basic conditions such as solid sodium bicarbonate in a suitable solvent such as N,N-dimethylformamide with R8X, where X is a reactive leaving group such as a halide or sulfonate to give 15. Additionally, 15 may be reacted with pyrocarbonates such as diethyl pyrocarbonate in a suitable solvent such as acetonitrile or N,N-dimethylformamide in the presence of a tertiary amine base such as N,N-diisopropylethylamine to give carbamates of either mono- or di- substitution on the amidino nitrogens as in 16 and 17 as well as tri-carbamates with additional substitution on the aminooxy nitrogen as in 18.
Scheme IV outlines an alternative synthesis of the target component 7 in Scheme I. In this alternative synthesis, the alcohol 19 is reacted with N-hydroxyphthalimide in a Mitsunobu reaction to yield 20. After the removal of the protecting group Pa, the key intermediate 21 and the phenol 4 are coupled in another Mitsunobu reaction to yield the intermediate 7.
The present invention a method of treating xcex1vxcex23 integrin- or xcex1vxcex25 integrin-mediated conditions by selectively inhibiting or antagonizing xcex1vxcex23 and xcex1vxcex25 cell surface receptors, which method comprises administering a therapeutically effective amount of a compound selected from the class of compounds depicted by FormulaIV, wherein one or more compounds of Formula IV is administered in association with one or more non-toxic, pharmaceutically acceptable carriers and/or diluents and/or adjuvants and if desired other active ingredients.
More specifically, the present invention provides a method for inhibition of the xcex1vxcex23 cell surface receptor. Most preferably, the present invention provides a method for inhibiting bone resorption, treating osteoporosis, inhibiting humoral hypercalcemia of malignancy, treating Paget""s disease, inhibiting tumor metastasis, inhibiting neoplasia (solid tumor growth), inhibiting angiogenesis including tumor angiogenesis, treating diabetic retinopathy, age-related macular degeneration, retinopathy of prematurity and other neo-vascular eye diseases, inhibiting arthritis, psoriasis and periodontal disease, and inhibiting smooth muscle cell migration including neointimal hyperplasia and restenosis.
The present invention also provides a method for inhibition of the xcex1vxcex25 cell surface receptor. Most preferably, the present invention provides a method for inhibiting angiogenesis associated with pathological conditions such as inflammatory disorders such as immune and non-immune inflammation, chronic articular rheumatism and psoriasis, disorders associated with inappropriate or inopportune invasion of vessels such as restenosis, capillary proliferation in atherosclerotic plaques and osteoporosis, and cancer associated disorders, such as solid tumors, solid tumor metastases, angiofibromas, retrolental fibroplasia, hemangiomas, Kaposi sarcoma and similar cancers which require neovascularization to support tumor growth. The present invention also provides a method for treating eye diseases characterized by angiogenesis, such as diabetic retinopathy, age-related macular degeneration, presumed ocular histoplasmosis, retinopathy of prematurity, and neovascular glaucoma.
The compounds of the present invention are useful in treating cancer, including tumor growth, metastasis and angiogenesis. For example, compounds of the present invention can be employed to treat breast cancer and prostate cancer.
The compounds of the present invention may be administered in an effective amount within the dosage range of about 0.01 mg/kg to about 300 mg/kg, preferably between 1.0 mg/kg to 100 mg/kg body weight. Compounds of the present invention may be administered in a single daily dose, or the total daily dosage may be administered in divided doses of two, three or four times daily.
The pharmaceutical compositions of the present invention can be administered to any animal that can experience the beneficial effects of the compounds of the invention. Foremost among such animals are humans, although the invention is not intended to be so limited.
The pharmaceutical compositions of the present invention can be administered by any means that achieve their intended purpose. For example, administration can be by parenteral, subcutaneous, intravenous, intramuscular, intraperitoneal, transdermal, buccal, or ocular routes. Alternatively, or concurrently, administration can be by the oral route. The dosage administered will be dependent upon the age, health, and weight of the recipient, kind of concurrent treatment, if any, frequency of treatment, and the nature of the effect desired.
In addition to the pharmacologically active compounds, the pharmaceutical preparations of the compounds can contain suitable pharmaceutically acceptable carriers comprising excipients and auxiliaries that facilitate processing of the active compounds into preparations that can be used pharmaceutically. The pharmaceutical preparations of the present invention are manufactured in a manner that is, itself, known, for example, by means of conventional mixing, granulating, dragee-making, dissolving, or lyophilizing processes. Thus, pharmaceutical preparations for oral use can be obtained by combining the active compounds with solid excipients, optionally grinding the resulting mixture and processing the mixture of granules, after adding suitable auxiliaries, if desired or necessary, to obtain tablets or dragee cores.
Suitable excipients are, in particular, fillers such as saccharides, for example, lactose or sucrose, mannitol or sorbitol, cellulose preparations and/or calcium phosphates, for example, tricalcium phosphate or calcium hydrogen phosphate, as well as binders, such as starch paste, using, for example, maize starch, wheat starch, rice starch, potato starch, gelatin, tragacanth, methyl cellulose, hydroxypropylmethylcellulose, sodium carboxymethylcellulose, and/or polyvinyl pyrrolidone. If desired, disintegrating agents can be added, such as the above-mentioned starches and also carboxymethyl-starch, cross-linked polyvinyl pyrrolidone, agar, or alginic acid or a salt thereof, such as sodium alginate. Auxiliaries are, above all, flow-regulating agents and lubricants, for example silica, talc, stearic acid or salts thereof, such as magnesium stearate or calcium stearate, and/or polyethylene glycol. Dragee cores are provided with suitable coatings, that, if desired, are resistant to gastric juices. For this purpose, concentrated saccharide solutions can be used, which may optionally contain gum arabic, talc, polyvinyl pyrrolidone, polyethylene glycol, and/or titanium dioxide, lacquer solutions and suitable organic solvents or solvent mixtures. In order to produce coatings resistant to gastric juices, solutions of suitable cellulose preparations, such as acetylcellulose phthalate or hydroxypropylmethylcellulose phthalate, are used. Dye stuffs or pigments can be added to the tablets or dragee coatings, for example, for identification or in order to characterize combinations of active compound doses.
Other pharmaceutical preparations that can be used orally include push-fit capsules made of gelatin, as well as soft, sealed capsules made of gelatin and a plasticizer such as glycerol or sorbitol. The push-fit capsules can contain the active compounds in the form of granules that may be mixed with fillers such as lactose, binders such as starches, and/or lubricants such as talc or magnesium stearate and, optionally, stabilizers. In soft capsules, the active compounds are preferably dissolved or suspended in suitable liquids such as fatty oils or liquid paraffin. In addition, stabilizers may be added.
Suitable formulations for parenteral administration include aqueous solutions of the active compounds in water-soluble form, for example water-soluble salts and alkaline solutions. Especially preferred alkaline salts are ammonium salts prepared, for example, with Tris, choline hydroxide, bis-Tris propane, N-methylglucamine, or arginine. In addition, suspensions of the active compounds as appropriate oily injection suspensions can be administered. Suitable lipophilic solvents or vehicles include fatty oils, for example, sesame oil, or synthetic fatty acid esters, for example, ethyl oleate or triglycerides or polyethylene glycol-400 (the compounds are soluble in PEG-400). Aqueous injection suspensions can contain substances that increase the viscosity of the suspension, for example sodium carboxymethyl cellulose, sorbitol, and/or dextran. Optionally, the suspension may also contain stabilizers.
The compounds of the present invention may be administered to the eye in animals and humans as a drop, or within ointments, gels, liposomes, or biocompatible polymer discs, pellets or carried within contact lenses. The intraocular composition may also contain a physiologically compatible ophthalmic vehicle as those skilled in the ail can select using conventional criteria. The vehicles may be selected from the known ophthalmic vehicles which include but are not limited to water, polyethers such s polyethylene glycol 400, polyvinyls such as polyvinyl alcohol, povidone, cellulose derivatives such as carboxymethylcellulose, methylcellulose and hydroxypropyl methylcellulose, petroleumn derivatives such as mineral oil and white petrolatum, animal fats such as lanolin, vegetable fats such as peanut oil, polymers of acrylic acid such as carboxylpolymethylene gel, polysaccharides such as dextrans and glycosaminoglycans such as sodium chloride and potassium, chloride, zinc chloride and buffer such as sodium bicarbonate or sodium lactate. High molecular weight molecules can also be used. Physiologically compatible preservatives which do not inactivate the compounds of the present invention in the composition include alcohols such as chlorobutanol, benzalknonium chloride and EDTA, or any other appropriate preservative known to those skilled in the art.
The following examples are illustrative, but not limiting, of the method and compositions of the present invention. Other suitable modifications and adaptations of the variety of conditions and parameters normally encountered and obvious to those skilled in the art are within the spirit and scope of the invention.